Signals, Signs and Pavement Markings · Pavement Markings
Single solid white line
A solid white line marks the right edge of the roadway or separates lanes of traffic going the same direction, including bicycle lanes. You can go in the same direction on both sides of this line (except the shoulder), but you should not cross it unless you need to avoid danger.
Important
If your car breaks down and need to pull off the road. You can drive across the solid white line on the right side of a highway.
Learn it with your state's rules
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